Factors Affecting and Optimization Methods used in Machining Duplex Stainless Steel - A Critical Review

Abstract

Due to exclusive universal value and usefulness, the combination of good mechanical properties and manufacturing characteristics, Stainless steel is an indispensable tool for design engineers to design components. In oil and gas companies, power plants such as nuclear and thermal, equipment’s used in chemical processing industries: such as heat exchangers, seawater processing industries, Pipeline systems, face an incredible and exceptional challenge and the most important one is the reduction of thickness due to corrosion. In order to overcome this complexity, researchers developed a metal called duplex stainless steel (DSS). DSS is a mixture of Chromium – Nickel – Molybdenum - Ferric alloys that consists of an equal quantity of Face Centred Cubic (FCC) - austenite and Body Centred Cubic (BCC) - ferrite grains. DSS is designed to provide improved corrosion resistance, primarily stress corrosion and chloride pitting corrosion and superior resistance to other standard austenitic stainless steels. The DSS material is very difficult to perform machining operations due to high austenite, nitrogen content, alloy composition, high strength, work hardening rate and toughness. High hardness requires high cutting force which tends to reduce machinability characteristics such as tool wear, surface finish, low MRR, etc. This review article provides an overview of the research conducted during last one decade by the researchers and the optimization methods used to examine the machinability characteristics of DSS to predict surface unevenness wear in tool, machinability, MRR and chip volume ratio. Furthermore, this article indicates an efficient means of machining behavior, future scope and the fruitful methodology for the successful machining of duplex stainless steel.